The present invention relates to an apparatus for drawing off or exhausting vapors kitchen equipment including at least one exhaust shaft running along one side of the kitchen appliance having a long, narrow suction or exhaust opening and a fan connected thereto by flexible air ducts.
It is known to draw off vapors which occur in connection with kitchen equipment, e.g. cookers, baking ovens, grills, deep fat fryers, etc. by exhaust or suction equipment. Such equipment mainly consists of holds, which are placed above the working surface at a distance such that working on the actual kitchen appliance is not impeded. Additionally, in, for example, DE-AS 1 579 679 ventilating means are proposed which have long, narrow draught flues directly alongside the working surface of the kitchen appliance, so that the vapors can be drawn in a downward direction. The fan can be positioned below the actual apparatus in a cabinet support or even at a greater distance therefrom. Such means have the advantage that the space above the kitchen appliance remains free and the vapor are drawn off closer to the point where they are formed, so that more effective purification of the air is obtained.
Generally a draught flue with a long and narrow exhaust opening is arranged on either side of the kitchen appliance. The exhaust opening is covered by a grating, so that it serves as a storage surface and, in the case of an adequately large free draw-off cross-section, avoids larger objects being able to drop into the draught flue. The latter also contains a sieve or filter for retaining particles, droplets contained in the vapor and the like.
A disadvantage of the above-described construction resides in the fact that if the outgoing air duct of the fan leads outside the building, when not in operation cold air can penetrate from the outside and exit through the exhaust openings, which is particularly unpleasant in winter. Moreover, when the kitchen appliance is not in operation, small articles, kitchen tools and kitchen waste or the like, when working on adjacent surfaces, can pass into the draught flue, so that the filter frequently requires dismantling.
The aim underlying the present invention resides in providing a construction for preventing a return flow of outside air in the case of a corresponding temperature gradient between the inner area and the atmosphere and which simultaneously prevents the penetration of foreign bodies into the draught flue when not in operation.
In accordance with advantageous feature of the present invention, at least one cover for an exhaust opening is provided on the draught flue with the covere being mounted so as to pivot between an open and a closed position and provided with a drive coupled to the fan on-off switch.
By virtue of the features of the invention it is possible to seal each draught flue in a vicinity of the exhaust opening. By coupling the drive of the cover with the fan on-off switch, it is ensured that when the exhausting means is not in use the cover is always closed. Thus, when not in use there can be a return flow of external atmosphere into the inner area, this particularly applying to cold air. It is also ensured that when the kitchen appliance or the exhaust fan is not in operation and consequently for the majority of the time articles, kitchen waste, etc. cannot drop into the draught flue. As the cover is given a planar surface, this leads to a smooth transition between the kitchen appliance and adjacent equipment or work surfaces, so that during the period of non-use, the user cannot get caught on gratings or the like with kitchen tools, pots, etc. When not in use, an esthetically satisfactory smooth surface is obtained, which can be more easily cleaned than a grating.
Advantageously, in a median longitudinal axis of the exhaust opening two covers are mounted which can be pivoted to opposite sides and which, in each case cover the entire length and half a width of the exhaust opening.
An advantage of the construction of the present invention resides in the fact that, in the case of an acceptably wide exhaust opening, the covers either do not project or only project slightly over the level of the adjacent kitchen appliance, e.g. over hotplates or the cooking surface of an electric cooker, so that work on the kitchen appliance is not impeded.
Preferably according to the present invention, the drive of the covers is so linked with the on-off switch of the fan, that, after switching off the fan, the covers close with a time lag.
The lag time can be set at random. The lower limit will be chosen in such a way that, after switching off the fan, the covers are not firmly drawn down by a vacuum which exists for a certain time period. This is also intended to ensure that even if switching on takes place immediately, the covers can be opened with limited driving force. If the fan is equipped with a servomechanism to enable it to continue running for some time after operating the manual off switch, then the covers will also only be closed at the end of this follow-up time, optionally, with the aformentioned additional lag. The fan servomechanism has the advantage that after manually operating the off switch, the user can leave the kitchen appliance or the room, although the fan continues to run for a certain time period and will only switch off at the end of the set follow-up time. In place of a delayed opening of the covers, it is also possible to have a delayed starting of the fan following the operating of the drive for the covers.
According to further advantageous feature of the present invention, the drive for the covers includes an electromagnet, which has an inexpensive construction and is also capable of applying the necessary control forces for the covers. However, it also possible to use a servomotor or the like.
According to additional advantageous features of the invention, the covers are detachably mounted on the draught flue, so that the latter can e.g. be removed for cleaning purposes and, for example can be cleaned in a dishwasher.
According to the present invention, each cover has on one end a stud and on the other end a coupling pin for the drive, whereby the latter can be inserted in a corresponding coupling sleeve on the drive and the stud can be placed in an open bearing box. The cover is inserted in simple manner in that initially the coupling pin is inserted in the coupling sleeve of the drive and is then placed with the stud in the open bearing box.
Finally, it is advantageous if the cover has, on its longitudinal side resting on the edge of the exhausting opening in the closed position, a damping material strip, e.g. an inserted O-ring. The latter avoids or greatly attenuates noise on closing the covers.
The invention is described in greater detail hereinafter relative to an embodiment and the attached drawings, wherein.